Limitations
This study has several limitations. First, we did not investigate the
ionic current characteristics of KCa3.1 channel by
patch-clamp technique. Further studies are required to address the
characteristics of KCa3.1 current and the effects of
KCa3.1 channel inhibitor on the KCa3.1
channel. Second, we determined the electrophysiological characteristics
and the expression of KCa3.1 in the PVs and SVC.
Triggered activity similar to PVs foci has been seen in the musculature
of other cardiac structures. Whether other sites, such as the
musculature of the coronary sinus and the ligament of Marshal, have the
same electrophysiological characteristics and KCa3.1
expression levels as the PVs is unknown. Third, we didn’t test the
effect of different concentration of TRAM-34 on the DAD and DAD-induced
trigger activity. This is the
limitation of this study.